Auxiliary operating mechanism for bicycles



Nov. 8, 1955 A. R. OBERWEGNER 2,723,132

AUXILIARY OPERATING MECHANISM F'OR BICYCLES Filed Dec. 20 1951 '1111 Lwill,

4/ I N V EN TOR: //e o/ i? @6e/waywar- V BY y ma@ @n United StatesPatents O nuxlunkv OPERA-irme MEeHnNIsMFon BICYCEESl My invent-ion.relates generallyf to, vehicles; and' more particularly to. ai bicycleand driving.v means` fon rotatingthe drivingV wheelthereof'.ySpecifically, the, inventionfpertains. tol a. compound' crank-v motionor operating.; means.

means actuatedi by a second rider-v on the bicycle for'increasing thetorque developedlbythe conventional crankmotion.

Tandem bicyclesv have been. used. quite extensively. in.v

thepastfor. conveying two passengers, suchbicycleshaw ing apairof crankseach operated by. afrider, thefcombinedeforts ofV the two ridersproducingtliev energy required.to-prope1`the` bicycles, alongfthe roadWhile such tandem bicycles are quite popular atresorts orvacation areasthey have severall disadvantages. which., practicallyl prohibit their,use. in congested areas. One of these disby advantages i'stliat. such acycle is long heavy, .andcumbersome. ln addition,.such a vehiele. noteasily, maneuvered on the roadV and. is wholly unsuitablel for use by. asingle riderl since'the` energy exerted by. one rider` isV hardlysufficientI to propel the, heavy` bicycle.`

It is qui-te common practice for? the rider. of! a, con ventionalbicycle to takeV alongY apassenger who, usually;V sits on the luggagecarrier disposed at." the rear. of. the riders seat, Such a passengerobtains a freeride since he does not contribute energy for propellingthebicycle. Thus', the driye'r` must exert' energy far' in excessioffthatnormally required.' to propel the bicycle when-he alonei's riding, thesame.

lt is an' object of my; invention to provide a. bicycleof conventionalsize havinga compoundl cranio-motionA for rotatingth'e'reardrivingwheel; said cranio motonfbeing operable by eitherone or tworiders so thatwhen, afsecondperson islb'eingj transported'hemay helpto'operate thecrankl motion" and'. thus apply the additional` torquet'o' thel driving" Wheel necessary to compensate for his weight.

Another object is to provide in a bicycle having aconventio'nalyrider-operated'- pedal crank,v an auxiliary operating"means which is s'o connected to said crank that power exerted3 by the`second` rider upon this operating means is transmitteditotheconventionalicrank and'thence to the drivingfwheel through the mediumof `a chain and sprockets; or other power' transmission means.

Another object isto" provide an auxiliary operating meanswhichpreferably in' the form of an attachment .'vliich may be readilyapplied` t'o andi removed from a conventional bicycleL so asto convertthe'` bicyclev from a one-passenger vehicle't'o a two-passenger ortandem, type bicycle; or viceversa, as'. desired. A relatedobjectistoprovide'such anattachment which may be-appliedto-any conventional'bicycle. without' altering the structure,- thereof and by: the use. of asingle'wrench.

Another object isto. provide anr auxiliary,- operating means whichincludes a lever-armhaving one: end piv otally connected'to theaxle-ofvthe-drivingnwheel, a` link 2,723,132 Eatented Nov. 8, 1955 ICChaving one end pivotally connected to the free end, ofthe lever` arm,land its. other; end-` pivotally connectedA to the freel end.` of the;conventional cranky arm ofi' the bicyc1e preferably' aty the'` axisofrotation ofVv the pedal mounted thereon, and: a: pedab rotatablyconnected tothe linkintermediate its@ endsv I- naccordance with theinvention; the auxiliaryoperating-l me1an`s is` providedf in duplicate,one' arranged at each5sid'e of thezbicycle andconnectedto one of thecrankv arms of` the bicycle.

A' further objectvr isf tof provide an: auxiliary operating means whichincludes;wearfresistantl bearings aty the'pivotal connections so( astoyr'educe the force necessary to operate the means and to. minimizewear between the components;

A further object is to provide an auxiliary operating means, ofthefcharacter'- referredl to,- inrwh'ich tlie link is preferablyarticulated, the two' parts; of' the link: being joined by at connectingpin so that by simplyy removingy the pin,y the auxiliary operating;means is rendered inoperative.

A further object-of theinvention-isto provide a tandem attachment' forconventional' bicycles whichv includes, in addition to the auxiliaryoperatingi means referred? tov4 above, a secondary on additional supportforl the second" rider onf the cycle.l `I naccordance Withthe present"concept, I provide asupport which is readily attached' to theconventional luggage carrier` overlying the driving wheel and` whichincludes; ai second seat. The support includes a post which.v projects;vupwardly froml a platelikev clampingemeans,y the saddlerbeingiadjustablysecured'r to this post.

Another object-4 is' to,` provide an auxiliar-yI operating means of thecharacter referredtoin-which' each auxiliary pedal carried by a,holder.I memberis pivotally' mounted thereon to. adaptthe pedal to: bepivoted tor an' operative position in which it projects laterallyoutwardlyffrom the link, and. toy a` retracted inoperative positionfwherein it extends, alongsidethe link. By this provision', theauxiliary'ped-alsmayI lne-retracted? when the auxiliary'operating'rneansfisnotI inuse A related? object-2' is to` provide detentmeans onthe link operative to retainl the holder member in either itsextended; or retracte'd positions;

A further object is to provide anauxiliary' operating means.inwhich.thelever arms: and links are constructed from channel.` stockAso' as: to render them light'in weight without. sacrificing. strength'.

A still further object is to provide a retaining means ons the frame ofthe bicyclev for holding the auxiliary operating. means infoldedY inperative4 position against' the frame after the links' have beendisconnected from the main cranks of the bicycle.

F urther` objectsw willy appearfrom theffollowingf description, andfrom: the drawing, which isintend'e'dfor the purpose of illustrationonly and' in` which:

Fig.,1A isa-sidevview of aY conventional' bicycle, showing my tandem orauxiliary operating means'appliedthereto;

Fig. 2 is an enlargedy sectional planview ofthe operating. link of theauxiliary drive, takeny onL line 2"-,2` of Fig.V 1;

`Fig.3 is aiverticaltsectionalview; taken online 3 3" of Fig. l,showing: thevpivotal connection' for the" operating link at themaincrank ofthe bicycleg.

i AFig.A 4 isa vertical'sectional:viewtalienion line- 4`4f of Fig. 1'; FFig. 5 is ay crosssectional view, taken onfline=5'-5 of Fig. 6 is asimilar view, takenl on line-6 6 of Fig. 2;

u Fig; l is a fragmentary view of a portion of theioperat'- mg link,showing graphically the path of movement of the auxiliary pedalcarriedby the link;.

Fig.l 8is a vertical' sectional view ofthe auxiliary seat, connection,takeno'n lines-8 ofFig.. 1';

Fig. 9 is a plan view of the hand-grip means employed by the rear rider,and

Fig. 10 is a cross-sectional view, taken on line 1li- 1li of Fig. l.

Referring to the drawing in detail, my auxiliary operating means 10 isshown as applied to use in connection with a conventional bicycle whichhas a frame 12, a front steerable wheel 13 carried by the usual fork 14,a seat 15 for supporting a rider, and a rear driving wheel 16. The wheel16 is rotated to propel the bicycle along a roadway by means of aconventional crank Ztl which is rotatable in a crank bearing formingpart of the frame 12. The crank 2l) has oppositely extending crank arms21 and 22 and a sprocket 23 which drives a smaller sprocket 24 on theaxle, or coaster brake, of the wheel 16 through the medium of a chain25, the crank arms carrying pedals 26 by which the crank can be manuallyrotated in the usual manner. f

Pivoted on the opposite ends of the axle 27 of the rear wheel 16 arelever-arms 3i), one at each side of the bicycle. Each lever-arm may bemade from channel stock to render it light in weight, yet strong anddurable in use. Each lever-arm is pivoted to the axle in the mannerillustrated in Fig. 4, to which view reference is now made. At its upperend, the lever-arm 30 is provided with a boss 32 having a hole intowhich a sleeve 33 is forced. A journal element 35 is screwed onto theouter threaded end of the axle or spindle 27 and has an inner,sleeve-like shank 36 which is set up against the rear fork portion 37 ofthe bicycle frame 12.' The shank 36 extends through the sleeve 33 toprovide a support for the lever-arm 36 which pivots thereon. The element35 has a head 38 which acts to retain the lever-arm in place. Theelement 35 thus is substituted for the usual spindle nut whichordinarily is screwed onto the spindle or axle to retain the axleassembly in adjusted position on the rear fork of the bicycle frame, theelement additionally providing a journal for the lever-arm. Since theaxle spindles of American and English made bicycles have different screwthreads, elements 35 having the appropriate threads are provided.

At its lower end, the lever-arm 30 has a boss 40 provided with a bearingthrough which extends the shank of a bolt 41. Pivoted on the bolt 41 isthe rearward end of an operating link 42. A head 43 of the pivot bolt41abuts one side of the arm 3l) and a nut 44 is screwed onto the other endof the bolt.

The forward end of the channel-shaped operating link 42. is providedwith a boss which is slotted to provide transversely-spaced hinge ears46 which interleave with similar hinge ears 47 provided at the rearwardend of a pivot element 48 (Figs. l and 2). The pivot element 48 and theoperating link 42 are detachably connected by means of a hinge-pin 49which extends through aligned holes in the ears 46 and 47, this pinhaving a bent end 5t) providing a handle by which the pin can be readilywithdrawn from the ears to permit disconnection of the parts 42 and 48for the purpose to be later explained.

The forward end of the pivot element 48 is pivotally connected to theouter free end of the crank arm 21, at the outer side thereof, as shownbest in Fig. 3. Referring to this view in detail, a stud has an endwhich is screwed into the usual threaded hole adjacent the end of thecrank arm 21, this hole usually receivingy the screw-threaded end of thespindle of a conventional pedal. The stud 55 has an enlarged portion 56which serves as a bearing or pivot pin for receiving the inner race of aball bearing 57, the outer race of which has a force t in a transversehole in the forward end of the pivot element 48. Thus, the pivot element48 is pivotally connected to the free end of the crank arm 21. The stud55 has a head 58 at its outer end which serves to retain the pivotelement 48 in place. Into a threaded hole in the outer end of the stud55 is screwed the threaded end of the spindle 59 of a conventional pedal26. By this arrangement of parts, the pivot element 48, forming theforward end of the operating link 42, is interposed between thecrank-arm 21 and the pedal 26 for pivotal movement on the axis ofrotation of the pedal.

The operating link 42 has longitudinal webs 63 which dene a recess 64 inthe outer side of the link (Figs. 2 and 5 A vertical cross-pin 65 (Fig.6) extends transversely across the recess between the webs, and pivotedon this pin is one end of a holder 66 in the form of a rectangularplate. Adjacent its free end, the holder 66 has a threaded hole intowhich is screwed the threaded end of the spindle 67 of an auxiliarypedal 68, of conventional form. During operation of the auxiliaryoperating means, the holder 66 assumes the position shown by full linesin Fig. 2 where it is disposed within the recess 64, at which time thepedal 68 projects laterally outwardly to its operating position. Whenthe auxiliary operating means is not in use, the holder 66 is pivotedthrough ninety degrees to the broken line position indicated in Fig. 2and the pedal is caused to assume a position adjacent the outer side ofthe operating link 42. A spring-actuated plunger 69, slidable in a block70, engages the holder 66 to frictionally retain the latter in either ofits two positions.

Referring to Fig. 1 of the drawing, it will be observed that anauxiliary operating means, such as described above, is provided at eachside of the bicycle. This dual operating means is adapted to bemanipulated by a rider who is seated on the bicycle over the rear wheel16 thereof. In order to support the rider comfortably, I provide a rearseat which, as shown, is mounted on the usual luggage carrier 76 of thebicycle. Referring to Fig. 8, the lower threaded end of a post 77extends downwardly through an opening in the luggage carrier 76. A firstclamping plate 79, screwed onto the post 77, rests against the topsurface of the luggage carrier, and a nut 80 screwed onto the lower endof the post and against a second clamping plate 81 draws the platestoward each other to grip the luggage carrier therebetween, thusretaining the post in place. The rear seat 75 is clamped to the upperend of the post 77 by any suitable means, the post being initiallyadjusted vertically by screwing it upwardly or downwardly in the plate79, after which the nut is tightened.

The rider supported by the rear seat 75 actuates the auxiliary operatingmechanism by manipulating the auxiliary pedals 68, and to steady thisrider, during propelling of the Vehicle, l provide a hand-hold 82 whichis, in effect, an auxiliary handle-bar. The hand-hold 82 is in the formof a rod or tube extending transversely of the bicycle at the rear ofthe main seat 15 and provided with hand grips at its ends. hand-hold 82has a pair of mounting strips 84 which extend forwardly under the seat15 where they are held by means of the usual screws 85 which fasten thecushionlike saddle to the frame of the seat.

Assuming that the bicycle is to transport two persons, one rider assumesa position upon the forward seat 15 with his legs straddling the bicycleframe and with his feet resting upon the opposite pedals 26, this ridergrasping the main handle-bar to steer the bicycle. The other ridermounts the bicycle by sitting on the rear seat 75 with his legsstraddling the rear wheel 16 and with his feet engaging the auxiliarypedals 68, which at this time assume the operative position shown byfull lines in Fig. 2. To propel the bicycle, the forward rider opcratesthe crank 20 in the usual manner to apply torque to the rear axlethrough the medium of the sprockets 23 and 24 and the driving chain 25.At the same time, the rear rider contributes to the torque applied tothe rear wheel by alternately pressing downwardly on the oppositeauxiliary pedals 68. That is to say, as each crank arm 21 and 22 rotatesto carry its pedal 26 forwardly across top center, the auxiliary pedal68, which is operatively connected to the particular crank arm, isforced downwardly by the rear rider.

This downward force is transmitted through the op- Referring to Fig. 9,the' arterias.

erating ,links 42. to the. crank arms. to. increase. the. torque appliedtoY the crank ZD andfftlius to. the* driving wlieel' I6 The second" orrearvrider. offtliis tandembicycle tlus contributes his. share. of. thepofwen required" to propel tlie bicycle. andA the.. energy usuallyexerted'b'y the front rider, when. lievv alone. propels thefbicyclecarrying two passengers, is materially: reduced,.that is to.approximately one-half the usual' energy. The' path of' movementl of'each of thev auxiliary pedals 68 is. in dicatedby,I the generallyelliptical curve inFig. 7. Byconsulting this curve, it is seen that therear riderexerts both' forward and downwardY forces Y alternatelyagainst.v eacll` auxiliary`-^ pedal during' thel operative stroke oilthe: corresponding` crank arm21 or. 221 During travel-offthe-bicyclein-tliis-'manner, the rear passenger remains comfortably seated on therearsaddle 75 and-maintains his-"equilibrium by grasping the `auxiliaryhandle-bar- 82.'

When thebicycle is tobe usedconventionally, that is, to transport onlyone person, the auxiliary pedals 68 may be folded to` their inoperativepositions, as indicated by the broken lines in Fig. 2 if ,d'esiredL IftheY bicycle normally i's used to convey one personW and onlyoccasionally to` transport two persons, the` auxiliaryt operatingmeans'may normally be disconnected., This is. readily accomplished bysimply removing the hinge-pinsvv 49 to disconnect the forward ends ofthe operating links 42 from their respective pivot elements 48. With thelinks 42 thus disconnected, they are swung upwardly on their pivots 41to position their upper ends against the brackets 90 which support theluggage carrier 76, see broken lines in Fig. l.

Headed screws 91 are carried by substantially U-shaped members 92, thelatter being adjustable vertically along the brackets 90 and retained inposition by the screws which are screwed through nuts 93, welded to themem' bers, and against the brackets 90, as shown in Fig. 10. The headedscrew 91 on each member 92 is adapted to be disposed between the ears 46of one of the operating links 42. After each link has thus beenpositioned, the pin 49 is inserted through the holes in the ears 46 toextend across the screw 91 and to engage the inner side of the headthereof so as to lock the auxiliary operating parts in their inoperativeposition. When the bicycle is to transport two passengers, the pin 49 iswithdrawn to allow the link 42 to be swung downwardly for connection toits pivot element 48. It is thus seen that the vehicle can be quicklyconverted from a single passenger bicycle to one of the tandem type, andvice versa, as desired.

When the operating links 42 are disconnected, the pivot elements 48remain connected to the crank arms 21 and 22 and merely hang pendulouslyfrom the studs 55, inwardly of the main pedals 26 so as not to interferewith the operation thereof. Besides providing a con Venient means fordetachably connecting the links 42 to the crank arms 21 and 22, thepivot elements 48, due to their hinge connection 49 to the links, allowactuation of the auxiliary operating means, even when the rear axle 27is out of parallelism with the axis of rotation of the crank 20. This isan important consideration since, by this articulated link structure,undue friction or binding action, which might impair free movement ofthe mechanism and cause wear of its components, is avoided.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with themechanism which I now consider to represent the best embodiment thereof.

I claim as my invention:

1. An auxiliary operating means for use in connection with a bicyclehaving a frame, a driving wheel, a crank arm rotatable on the frame andhaving a pedal rotatable at its outer end, sprockets connected with saidcrank arm and said wheel, and a chain extending around said sprockets,comprising: a lever arm pivoted on the axis of the wheel and having afree end; a pivot element pivotfI ally mountedon. said crank-arm atthe.yof' rotationyof its. pedal and.'y havingJ an end projecting fromA saidaxis,l sai'd end having spaced; perforated hinge ears;Y a link havingone end. pivotally' connected to. saidfi'ee end of said lever: arm andits. otherv end providedwitli spacedv perforated' hinge earsinterleaving with the hinge ears of said" pivot element; andY a hinge. pi'n .extending through all of said hinge ears, normal to the axis of'Vrotation. of said' crank arm, saidl hinge pinhaving a' relatively tightfit in said". ears and being,provided. with a bent end providing ahandle by"wh'ich the pin can be manually withdrawn from saidv ears, topermit disconnection of' said" link and said pivot element'.

2i A'n auxiliary operatingmeans'foruse in connection with a bicyclehavingla frarne a driving wheel, a crank arrn rotatable on the frameand` having a pedal rotatable at its outer end', sprockets'connectedwith said' crank ann and said wheel, and a chain extending'aroundsaidsprockets, comprisingz. a leverarm pivotedV on` the axis of thewheeland'lhavinga free end;.a stud4v carried'b'y said"crank arm andextendingparallel' to the axis of'. the same, said pedalf being carried'by said stud and coaxial" therewith; a pivot element pivotally mounted'on said studon the axisofrotationo said pedal' andthaving'anend'project# irrg-radiallyfiom-` said axis, said end having'spaced, perLforated hinge ears; a link having one end pivotally connected to saidfree end of said lever arm and its other end provided with spacedperforated hinge ears interleaving with the hinge ears of said pivotelement; and a hinge pin extending through all of said hinge ears,normal to the axis of rotation of said crank arm, said stud having ahead abutting a side of the pivot element and retaining the same axiallyin place.

3. An auxiliary operating means for use in connection with a bicyclehaving a frame, a driving wheel, a crank arm rotatable on the frame andhaving a pedal rotatable at its outer end, sprockets connected with saidcrank arm and said wheel, and a chain extending around said sprockets,comprising: a lever arm pivoted on the axis of rotation of the wheel andhaving a free end; a pivot element pivotally mounted on said crank armat the axis of rotation of its pedal and having an end projecting fromsaid axis; a link having one end pivotally connected to said free end ofsaid lever arm and its other end pivotally connected to said end of saidpivot element on an axis normal to the axis of said pedal; and a pedalrotatable on said link, intermediate its ends and on the longitudinalaxis thereof, by which force can be exerted upon said link tending toincrease the torque applied to the wheel by said crank arm, sprocketsand chain, said operating means also including a stud having anexternally threaded inner end screwed into a threaded hole in the end ofsaid crank arm, said stud having a shank portion on which said pivotelement is rotatable, and on outer internally threaded end, said firstmentioned pedal having a screwthreaded spindle screwed into said outerend of said stud.

4. An auxiliary operating means for use in connection with a bicyclehaving a frame, a driving wheel, a crank arm rotatable on the frame andhaving a pedal rotatable at its outer end, sprockets connected with saidcrank arm and said wheel, and a chain extending around said sprockets,comprising: a lever arm pivoted on the axis of rotation of the wheel andhaving a free end; a pivot element pivotally mounted on said crank armat the axis of rotation of its pedal and having an end projecting fromsaid axis; a link having one end pivotally connected to said free end ofsaid lever arm and its other end pivotally connected to said end of saidpivot element on an axis normal to the axis of said pedal; and a pedalrotatable on said link, intermediate its ends and on the longitudinalaxis thereof, by which force can be exerted upon said link tending toincrease the torque applied to the wheel by said crank arm, sprocketsand chain, said pivot element carrying a ball bearing; and a stud havingan externally threaded inner end screwed into a threaded sans# hole inthe end of said crank arm, said stud having a shank portion receivingsaid ball bearing so as to pivotally support said pivot element', and anouter internally threaded end, said irst mentioned pedal having ascrewthreaded spindle screwed into said outer end of the stud,

said stud having a ange abutting said pivot clement to' retain the sameaxially in place.

5. An auxiliary operating means for use in connection with a bicyclehaving a frame, a driving wheel, a crank arm rotatable on the frame andhaving a pedal rotatable at its outer end, sprockets connected with saidcrank arm and said wheel, and a chain extending around said sprockets,comprising: a lever arm pivoted on the axis of the wheel and having afree end; a pivot element pivotally mounted on said crank arm at theaxis of rotation of its pedal and having an end projecting from saidaxis, said end having spaced, perforated hinge ears; a link having oneend pivotally connected to said free end of said lever arm and its otherend provided with spaced perforated hinge ears interleaving with thehinge ears of said pivot element; a hinge pin extending through all ofsaid hinge ears, normal to the axis of rotation of said crank arm, saidhinge pin having a relatively tight t in said ears and being providedwith a bent end providing a handle by which the pin can be manuallywithdrawn from said ears to permit disconnection of said link and saidpivot element, said operating means also including retaining meansonvthe frame engageable with the hinge ear end of said link when thelink is disconnected from said pivot element and pivoted upwardly, so asto retain the link in an inoperative position.

References Cited in the le of this patent UNITED STATES PATENTS 568,862Miehle Oct. 6, 1896 602,162 Kellogg Apr. l2, 1898 788,794 Evans May 2,1905 913,446 Adams Feb. 23, 1909 1,045,220 Turner Nov. 26, 19121,091,405 Trambley Mar. 24, 1914 2,619,364 Carson Nov. 25, 1952 FOREIGNPATENTS 52,401 Germany Dec. 3, 1889 16,510 Great Britain of 1888 24,469Great Britain of 1895 378,397 Italy Feb, 7, 1940 411,892 Italy July 19,1945

